使用IIF动态更改SQL语句

Question

很简单的问题，但是让我呆了几个小时。

我想将“性别”字段更改为这样：如果性别为0，则为1；如果性别为1，则为2

这是我的代码：

Private Sub Run_Click()
    Dim db As DAO.Database
    Dim queryDef As DAO.queryDef
    Dim sql As String
    Dim fields As Variant

    Set db = CurrentDb
    sql = ""

    fields = Array("Name", "Gender", "Age")

    For Each queryDef In db.QueryDefs
        If queryDef.Name = "Q_List" Then
            db.QueryDefs.Delete "Q_List"
            Exit For
        End If
    Next

    sql = sql & "SELECT "
    For Each field In fields
        If field = "Gender" Then
            sql = sql & IIf([Gender] = 0, 1, 2) & " AS Gender, "
        Else
            sql = sql & "[" & field & "]" & ", "
        End If
    Next
    sql = Left(sql, Len(sql) - 2)
    sql = sql & " FROM T_Customer"
    Set queryDef = db.CreateQueryDef("Q_List", sql)

    DoCmd.TransferText acExportDelim, , "Q_List", "C:\customerdata\data.txt", True, , 65001

    MsgBox "Done!"

End Sub

问题是，IIF并不适用于所有数据行，但它会字面比较是否是字符串的Gender等于0整数，并且我所有的Gender行都变为2 ...生成的Sql如下：

SELECT T_Customer.[Name], 2 AS Gender, T_Customer.[Age] FROM T_Customer

需要帮助请

解决了！！！

通过在sql语句IN STRING中编写IIF，并使用相同的字段名称，应这样编写：IIf（[tablemame]。[Gender] = 0，1，2）＆“ AS Gender，”

Answer 1

我认为您已经省略了两个引号。 对象循环中if之后的行应为：

sql = sql & " IIf([Gender] = 0, 1, 2) " & " AS Gender, "

现在sql变量是

SELECT [Name],  IIf([Gender] = 0, 1, 2)  AS Gender, [Age] FROM T_Customer